Selective formation of C60F18(g) and C60F36(g) by reaction of [60]fullerene with molecular fluorine

Fluorination of C₆₀(s), C₆₀(s)-MnF₂(s), C₆₀(s)-NiF₂(s) and C₆₀(s)-MnF₃(s) mixtures has been studied by Knudsen cell mass spectrometry with admission of molecular fluorine. The fluorination is selective when fullerene reacts with the fluorine chemisorbed on the MnF₂ surface. When the MnF₂ content in the initial mixture is at least 90 mol% both C₆₀F₁₈ and C₆₀F₃₆ are selectively formed. Under certain conditions, mixtures predominantly containing one of three compounds C₆₀F₃₈, C₆₀F₄₀, and C₆₀F₄₂ can be obtained. A consecutive change of the main fluorination products (C₆₀F₁₈ and C₆₀F₃₆) takes place at constant temperature (720 K) and on fluorine admission. A quantitative explanation of this fact is given. Selective fluorination of C₆₀(s) by molecular fluorine is compared with solid-phase fluorination using MnF₃(s) as a fluorinating agent.     

Development of Heteropolysiloxane Coatings on Electrogalvanized Steel

The development of heteropolysiloxane coatings on electrogalvanized steel by sol-gel processing has been studied from the sol state to the solid state using techniques such as 29Si NMR, SIMS, XPS, and the three point flexure test. It was possible, from the results obtained, to propose a simplified model for the coatings which brings into play two layers of differing molecular structure: an extremelly thin internal layer and an outer layer, respectively called the anchoring and volume layers.     

Calixarene/pillararene-based supramolecular selective binding and molecular assembly

This review mainly summarized the recent researches on the supramolecular selective binding and molecular assembly based on calixarene and pillararene. Several representative examples were provided to expound the progress in the area of recognition and sensing, multi-functional assembly and crosslinked multi-dimensional materials.     

Silicone glue based solid phase microextraction fiber for amino acid determination

A solid phase microextraction fiber based on high temperature silicone glue coated on a stainless steel wire is presented for use in the extraction of amino acid derivatives. Amino acids were derivatizad using ethyl chloroformate. Effects of the extraction and desorption parameters including extraction and desorption time, desorption temperature and ionic strength on the extraction/desorption efficiency have been studied and quality parameters of the method were measured. A possibility to apply the proposed method for the identification of proteinaceous binders was demonstrated.     

Selective oxidation using catalyst electrodes supported on solid electrolyte

The major oxygenated products of the selective oxidation of 1-butene by using a catalyst electrode were maleic anhydride on V₂O₅/YSZ/Ag and butadiene on MoO₃–Bi₂O₃–Ag/YSZ/Ag. Their selectivities were enhanced as compared with the non-electrochemical system.     

缓蚀剂在阳极电泳涂装中的应用

在电泳涂装工艺中使用缓蚀剂，可提高阳极电泳涂层的防腐蚀性，实验表明，沥青电泳漆与缓蚀剂的电泳共沉积涂层对基底金属具有较高的防护性能，探讨了共沉积涂层中缓蚀剂的缓蚀机理。     

Free release static coating of glass capillary columns; rapid coating at lower temperatures and elevated pressures

The coating speed upon static coating of glass capillary columans was evaluated in terms of inner diameter and length of the column, viscosity and pressure of solvent vapor, etc. From the equation obtained it can be shown that a smaller diameter of a microbore column restricts solvent vapor transfer to the orifice of the column drastically. To compensate for this restriction, a higher pressure at the meniscus is needed. As an alternative to using a higher coating temperature, application of more volatile solvents such as n-butane and isobutane is proposed. Several glass capillary columns (130 μm i.d.) were coated with SE-54 dissolved inpentane-acetone mixed with n-butane or isobutane and the column performances were evaluated. Selection of these solvents permitted free release static coating of ca. 100 μm columns at lower or even ambient temperatures and they were equally suitable as commonly applied solvents (e.g. pentane) to coat highly efficient columns.     

Catalytic Effects of Aluminum Butoxyethoxide in Sol-Gel Hybrid Hard Coatings

Hybrid inorganic-organic hard coatings on PMMA substrate were obtained by sol-gel reaction of 3-glycidoxypropyltrimethoxysilane(GPTS), tetramethyl orthosilicate(TMOS) and aluminum butoxyethoxide (Al(OEtOBu)₃). The catalytic effect of aluminum butoxyethoxide on inorganic condensation and epoxide polymerization has been studied by ¹³C, ²⁹Si nuclear magnetic resonance spectroscopy and by Fourier transformed infrared spectroscopy. Hardness of hybrid inorganic-organic materials were measured by nanoindentor and mainly influenced by the extent of epoxide polymerization and inorganic condensation of their coating catalyzed by aluminum butoxyethoxide.     

Phenomena Involved in Suspension Plasma Spraying Part 2: Zirconia Particle Treatment and Coating Formation

The first part of this paper was devoted to phenomena related to liquid injection in the Suspension Plasma Spraying (SPS) process. This second part emphasizes the solid particles treatment and the coating generation. A simplified theoretical approach is proposed to evaluate the influence of the numerous experimental parameters on heat and momentum transfers from the plasma jet to individual particles. It is shown that small solid particles vanish by vaporization and are very sensitive to plasma arc fluctuations and thermophoresis effect, which makes particles to escape from the jet. This study is completed by experimental investigations concerning, first, in-flight collection of particles and, second, coating elaboration. The importance of the particle size distribution of the injected powder and the parameters for the plasma generation is demonstrated, as their choice can give either porous or dense coatings.     

As-V-O簇合物对乙苯选择氧化反应的催化活性

通过水热方法合成了簇合物［Ｎ（ＣＨ３）４］４［Ａｓ８Ｖ１４Ｏ４２（８Ｈ２Ｏ）］及其相近的同多及杂多钒氧簇Ｋ６Ｖ１０Ｏ２８·９Ｈ２Ｏ，ＮａＫＶ２Ｏ６，（Ｈ２Ｅｎ）０．５Ｖ２Ｏ５，（Ｈ２Ｅｎ）３（ＶＯ）９（ＰＯ４）８，Ｎａ３ＶＯ（ＨＰＯ４）（ＰＯ４）·Ｈ２Ｏ．运用ＸＲＤ和ＩＲ等手段表征了［Ｎ（ＣＨ３）４］４［Ａｓ８Ｖ１４Ｏ４２（８Ｈ２Ｏ）］的结构．该类化合物对于催化乙苯过氧化氢选择氧化制苯乙酮具有较高的催化活性．通过比较含钒与不含钒化合物的活性情况，讨论了催化氧化的活性中心．